Recent developments in telecommunications have resulted in broad band communication networks with subscriber lines formed by means of light waveguides. A star network of light waveguides with one light waveguide per dwelling unit has proven, expedient at the subscriber level. The light waveguide connects a central distribution or switching location (preferably spatially united with the nearest telephone switching location) to the dwelling unit of the subscriber and via which, under certain conditions, all telecommunication services for the corresponding dwelling unit can be sequenced. This permits, at least approximately, the following broad band communication possibilities for a dwelling unit:
three video channels for three video receivers with independent access to all TV signal sources which can be reached by the distribution system or switching location, or with independent access to all TV programs available there, PA0 under certain conditions, three return channels for program selection; and, under certain conditions, sequencing for interactive services as well as 20 VHF stereo radio channels (NTZ, Vol. 32 (1979), No. 3, pages 150-153; Antenna Information No. 63, June 1979, pages 3-5.
For transmitting a plurality of video signals or, respectively, of data signals from a preferably central transmission location via a light waveguide connection to a reception location, it is known (from the German OS No. 2,538,638 or, respectively, German OS No. 2,426,363) to convert the video signals or, respectively, data signals into pulse-modulated signals and to transmit these in time-division multiplex via the light waveguide connection.
If, given a broad band communication system of approximately the type outlined above, one is confronted after a time-division multiplex transmission of video signals with the task on the reception side of distributing the plurality of TV signals transmitted in the time-division multiplex to a corresponding plurality of receivers provided at the subscriber, then one could conceive of first regaining the original video signals and then supplying them to the individual receivers in respective video frequency position via receiver-individual lines or, converted into different frequency channels with the assistance of amplitude modulators, via a common distributor line. However, both ways require a relatively high outlay, whether it be of special distribution lines, or whether it be of special amplitude modulators. The invention reveals a way to avoid this.